[Clayart] Sad - Glaze stuck lids, no hope. My Bad!
Dan Saultman
Thanks to you all for trying to help. But alas I didn't wax resist far
enough down the inside of the jars gallery. They were "Glaze stuck"
with no hope.
I inspected each one as I broke them up. All day I muttered, " 8 out
of 9, 8 out of 9, 8 out of 9"
Losing 8 lidded pieces with hand turned knobs is a terrible hit. 24
pieces lost if you count all of the parts - so much work! (oh, I
managed to save a few lids)
Why I would expose my errors to the group escapes me. But I have
learned my lids lesson - a bitter lesson to be sure.
Maybe this will help someone else.
In the past these jars were fired separately from their lids. But they
had been distorting slightly and required major grinding for some to
fit.
Now I ask myself which way to go, fired on lids or fired separately.
Thanks for listening.
Dan
Dan Saultman
Fine-Art Pottery & Tile
ETSY Shop: http://www.etsy.com/shop/DanSaultman
Clinton Township, MI
http://www.saultman.com
Terrance
Terry
Sent from my iPad
Dorothy Parshall
Dorothy, Ontario
David Hendley
lids in place. There is no future in you trying to determine if it is better
to fire lids on or off their jars. It's settled, they need to be fired on
the
jars because otherwise, as you already found out, you risk ending
up with ill-fitting lids because of pyroplastic distortion.
I'm very sorry for your expensive and discouraging lesson from
the school of hard knocks. All of us who have a long history with
stoneware pottery have undoubtedly been similarly schooled. I
know I have.
For special situations, I do fire a few lids separately and it works
OK. I mostly do this with my lidded mugs because I want the rim
of the mug, where the mouth goes, to be fully glazed. As long as
the lid is under about 4" in diameter I have no problems with ill-
fitting lids. It still doesn't seem quite right for the glazed surfaces
of the mug and its lid to be in contact, but this is the best procedure
I've come up with. Once the lid is much bigger than this, you are
very likely to end up with an unacceptably high percentage of
warped ill-fitting rejects. I've also learned this "the hard way"!
David Hendley
da...@farmpots.com
http://www.farmpots.com
Gayle Bair
same for the lid (note I carefully measured the depth of the butter chamber
so it won't be deep enough to stick to the bowl). You could use just a
popsicle stick and mark the spots and forever have uniform non-stuck lids
unless you get sloppy with your glaze like I did once! I tried firing them
seperately but had some warping issues. Aluminia in my wax resist has done
the trick.
Gayle
Gayle Bair Pottery
ga...@claybair.com
www.claybair.com
On Thu, Sep 1, 2016 at 9:23 AM, Dorothy Parshall <doro...@whidbey.com>
wrote:
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KATHI LESUEUR
Exposing your errors isn't a problem. We all do things that make no sense. That's how we learn. In the past I fired all of the lids on my pots. Now, I fire drop in lids separately. I've never had a problem with fit. I do fire them on in the bisque to help stop warping. You might try that.
KATHI LESUEUR
http://www.lesueurclaywork.com
On Aug 31, 2016, at 8:05 PM, Dan Saultman wrote:
Vince Pitelka
"I am not big on tech knowledge but many years ago stuck lids led me to fire lid and jar separately. Large lids, such as butter dish, warp but this could be solved with that stuff people put on shelves to allow movement (alumina...?) I solved it by waxing a spot in the top of the lid, where the butter is unlikely to touch, and putting each on a post just high enough to not touch the shelf. They do not warp and the bottoms are glazed in the gallery (?) rather than raw. Small lids fire just fine and fit in such wonderful little spaces between larger pots. No more stuck lids."
Hi Dorothy -
Are you sure that your claybody is truly vitrified at your glaze-maturation temperature? Because the reason most of us never fire lids and vessels separately is that they almost always warp, and you end up with a poorly-fitting lid, or a throwaway piece. In my experience it simply is not worth it. You always want a clay-to-clay contact surface, because a glaze-to-glaze fit on a lid just feels and sounds all wrong. A clay-to-clay contact gives a much tighter seal, but only if the lid is fired in place. If the lids are made properly with a taper fit, and if proper precautions are taking in waxing the contact surfaces and removing the residual glaze droplets, and if the glazes are under control so they do not run, then the lids always come off with little effort.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpit...@dtccom.net
Vince Pitelka
"Now I ask myself which way to go, fired on lids or fired separately."
Hi Dan. You already answered that question. You figured out what you did wrong, so stop doing that, and fire the lids in place. No problem. As I said in a message to Dorothy, if the lids and seats are made with a proper taper fit, if the entire contact surface is waxed, and if the residual droplets of glaze are removed from the waxed area, and as long as the glazes do not run and foul the contact, it will never be a problem to remove the lids. Even at the intro level I teach my students to wax properly and remove the residual droplets on their covered boxes, and the only time we ever have lids that will not come off with a mild tapping is when they have applied a glaze too heavily and it runs and seals the joint. Then there's nothing you can do but break the thing open and see what went wrong, just as you did.
Dannon Rhudy
first or second ceramics class. I was woefully aware
of how a poorly-fitting lid ruined a pot, and equally
aware of glazed-stuck lids. I was only just
learning to throw, and was determined to make some
lidded soup bowls. Alas. My glazing skills were not
really any better than my throwing skills. I tried
several different things, with minimal success. Then
someone -or maybe a book- was talking about using
colored slips for design work etc. It occurred to me
that I might be able to use a slip for the edge of
the lid, and the gallery. Then they'd look good, and
I could wax up higher without an ugly edge, etc. Sigh.
My besetting sin of impatience beset me once again.
Without further research I took a "set" of four lidded
bowls, brushed slip on the edges & galleries, waxed,
finished glazing, carefully wiped glaze drops out
of crevices, etc etc. Put them in a cone 10 fire, smiling
smugly to myself because I'd solved that problem by myself.
Only, I didn't. The slip I made/used, was in fact a slip-glaze,
and at cone ten it melted sufficiently to develop a slight
sheen. Very attractive. And a perfect glue to keep those
lids on forever. I kept one of those pots for years, as
a reminder that quicker isn't automatically better. And
that just a bit more reading would have informed me of
what I needed to know. But learning the hard way isn't
all bad. I'll never forget that lesson. It's stood me in
good stead now and again.
regards
Dannon Rhudy
Dale Neese
I echo what Gayle mentions. Works most all the time for me.
Dale Tex
"across the Alley from The Alamo"
Helotes, Texas USA
www.daleneese.com
Tommy Humphries
This method also works well for opening pop and beer bottles!
Tommy Humphries
Sent from my iPad
Dorothy Parshall
Definitely vitrified. I swear by, never at, my Tucker's clays. Another reason I do this is so the jar, with drop in lid, can stand alone when the lid is broken, as so often happens. I tend not to do it with lids that sit on a gallery, I guess, because, as you say, it does not make a good effect and, of course, that type of jar will never stand alone; the lid will always be noticeable missing! I did manage to make a new one, for a good guy, that fit the old pot - using my measuring tools, a green but dry, a bisqued replica as well as one fired to cone 6, of a ruler are useful for those times when ...
So I need to revise: drop in lids versus those with a gallery receive differing treatments. As Kathi says, bisqued together they tend not to warp in glaze firing.
All your "if"s are good to keep in mind. A "tapered fit" has never occurred to me! No wonder I have a bunch of lids that need pots to fit them! Thanks to clayart, I no longer work alone.
Dorothy, Ontario